Compact biometric acquisition system and method

ABSTRACT

A method of determining the identity of a subject while the subject is walking or being transported in an essentially straight direction is disclosed, the two dimensional profile of the subject walking or being transported along forming a three dimensional swept volume, without requiring the subject to change direction to avoid any part of the system, comprising acquiring data related to one or more biometrics of the subject with the camera(s), processing the acquired biometrics data, and determining if the acquired biometric data match corresponding biometric data stored in the system, positioning camera(s) and strobed or scanned infrared illuminator(s) above, next to, or below the swept volume. A system for carrying out the method is also disclosed.

RELATED APPLICATIONS

This application is a continuation of and claims priority to U.S.application Ser. No. 13/797,258, filed Mar. 12, 2013, entitled “COMPACTBIOMETRIC ACQUISITION SYSTEM AND METHOD”, which is a continuation of andclaims priority to U.S. application Ser. No. 12/441,881, filed Mar. 18,2009 entitled “COMPACT BIOMETRIC ACQUISITION SYSTEM AND METHOD” issuedas U.S. Pat. No. 8,965,063 on Feb. 24, 2015, which is a national stageentry of International application PCT/US2007/79160, filed Sep. 21,2007, entitled “COMPACT BIOMETRIC ACQUISITION SYSTEM AND METHOD”, whichclaims priority to U.S. provisional application 60/826,560 filed Sep.22, 2006, entitled “COMPACT BIOMETRIC ACQUISITION SYSTEM ANDARCHITECTURE”, all of which are hereby incorporated by reference for allpurposes.

BACKGROUND OF THE DISCLOSURE

This invention relates to biometric acquisition, identification, frauddetection, and security systems and methods, more particularly biometricsystems and methods which employ iris recognition, inter alia. Biometricacquisition systems generally employ cameras, lens, illumination,processors, and reporting functions. When such systems detect theidentity of a subject, they can issue a signal, open a gate, sound analarm, alert operators, or merely record the detection. Some biometricacquisition systems require a card swipe or other means of informing thesystem of the purported identity of a subject.

Previous systems were primarily kiosk-based, where the cameras andillumination were directly in front of the user, looking directlytowards them.

More recently, “walk through” biometric identification systems have beendisclosed. Walk through systems are designed to verify the identity ofsubjects who pass through an opening such as an airport gate, a door, orthe like, by illuminating the subject as it passes through the gate,acquiring an image of one or two irises and/or facial features of thesubject, applying an algorithm to an image to generate a set of data,and comparing the resultant set or sets of data to stored sets of datausing pre-designated criteria and determining if there is a matchbetween the sets of data and thereby determining if there is a matchbetween the subject's iris and/or facial features and registeredidentities. In the prior art systems, the cameras were mounted in adevice situated directly facing the user, such that the user had to walkaround the cameras.

There are problems with existing systems which have prevented them frombeing widely adopted. The great disadvantage of the arrangement ofilluminators and cameras is that the person has to stop or change theirdirection of motion, or else they will strike the cameras andilluminators. This approach has been the state-of-the-art in irisrecognition for decades. Also, when the illumination in prior systems iscontinually turned on at normal levels, the illuminator must be replacedat frequent intervals. Also, the systems may be fooled into illuminatingwhen non-subjects walk past them rather than subjects walking throughthem.

Some systems use multiple sensors to acquire data through spectralfilters at the same time, which is inefficient.

Further, some systems are not capable of integrating non-biometricdevices such as classic identification card systems which can be swipedor touched to a detector.

There has been a long-felt need in the field of biometric detectionsystems and methods for more efficient and effective detection,identification, and security.

SUMMARY

These needs and others as will become apparent from the followingdescription and drawings, are achieved by the present invention whichcomprises in one aspect a system for determining the identity of asubject comprising a system for determining the identity of a subjectwhile the subject is walking or being transported along in anessentially straight direction, the two dimensional profile of thesubject walking or being transported along forming a three dimensionalswept volume, without requiring the subject to change direction to avoidany part of the system, adapted to acquire one or more biometrics of thesubject and determine if the acquired biometrics match correspondingbiometric data stored in the system, the system comprising one or morecameras and one or more infrared illuminators which are strobed orscanned, wherein the cameras are positioned above, next to, or below theswept volume; and the illuminators are positioned above, next to, orbelow the swept volume.

In another aspect, the invention comprises a method of determining theidentity of a subject while the subject is walking or being transportedin an essentially straight direction, the two dimensional profile of thesubject walking or being transported along forming a three dimensionalswept volume, without requiring the subject to change direction to avoidany part of the system, comprising acquiring data related to one or morebiometrics of the subject with the camera(s), processing the acquiredbiometrics data, and determining if the acquired biometric data matchcorresponding biometric data stored in the system, positioning camera(s)and strobed or scanned infrared illuminators above, next to, or belowthe swept volume.

The invention results in an order-of-magnitude increase in thethroughput of people that can be processed by such a system. Thesubstantial gain in throughput can be measured by time-and-motionanalysis, and we have shown that the traditional systems where usersfaced cameras or lighting resulted in delays from having to find thekiosk or location to stop, wait for the prior person, putting down bags,reading instructions, waiting for the device to operate, picking upbags, finding the new direction in which to walk, and then walking tothe new location. Even if each of these steps takes 2 seconds, then thecumulative time to perform biometric reading can take 10 seconds ormore.

In one preferred configuration, the user looks at the camera as theywalk, the lighting and cameras are not co-located since the user may bewearing glasses. In addition, the lighting and cameras should not be toofar away from the user or else the signal/to/noise ratio of the imagewill be too low for acquisition of biometric imagery of sufficientquality for matching. Further, in embodiments of the invention where theuser looks straightforward or at arbitrary points that are notnecessarily the camera location, then the angle of the eye to the camerashould not be too large or else image foreshortening will result in asmaller-than-required segment of the iris being captured. It ispreferred that the lighting and cameras match the physicalcharacteristics of doorways and other locations through whichindividuals walk through.

Another aspect of the invention is a system for determining the identityof a subject walking or being transported in an essentially straightdirection comprising a motion sensor and an illuminator adapted to beturned on when motion is detected.

A still further aspect is placing the camera above, next to, or below adoorway or portal and acquiring the biometric data when the horizontaldistance between the subject and at least one of the cameras is between97.28 and 201.93 cm.

In applications wherein at least one camera is positioned on a counterand is used in a point of sale identity verification application and thehorizontal distance between the camera and the area of biometricacquisition on the subject is preferably about 0.15 to 1.2 meters.

In another aspect of the invention is determining the identity of asubject comprising employing at least one camera and at least oneilluminator adapted to illuminate at a level sufficient to detect thepotential presence of biometric data and upon detection to illuminate ata high level sufficient to acquire biometric data with improved signalto noise.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 illustrates a Subject walking towards camera and illuminationunit mounted above a doorway or portal;

FIG. 2 illustrates swept volume of person.

FIG. 3 illustrates Subject walking towards camera and illumination unitmounted to the side of a doorway or portal

FIG. 4 illustrates Subject walking towards camera and/or illuminationunit, and camera and/or illumination unit mounted on either side of adoorway or portal

FIG. 5 illustrates Subject walking past camera and illumination unitmounted to one side of the person's swept-volume

FIG. 6 illustrates a subject walking along path towards camera andillumination unit suspended from above by mount at a distance from theground, such that the camera and illumination unit is free standing andhas no contact with the ground.

FIG. 7 illustrates Area of biometric acquisition with the subject insideacquisition area

FIG. 8 (Comparative) illustrates traditional stroboscopic illuminationthat illuminates the whole area.

FIG. 9 illustrates non-stroboscopic, constant illumination in a smallerarea of dimension that is scanned over whole area in direction D suchthat light is only on the eye area for a fraction of the time as instroboscopic illumination, but many fewer illuminators are required, andhigh-power pulsed operation which is stressful to the LED is notrequired

FIG. 10 illustrates a two dimensional scan pattern of constantillumination following a path within an area of biometric acquisition,with subject inside the area of biometric acquisition.

FIG. 11 illustrates a preferred method for creating the scan pattern inFIG. 9, using an illuminator, a tilted mirror which is rotated using anelectric motor, showing how at 0 degree rotation light from theilluminator is projected at the top of the area of biometricacquisition.

FIG. 12 illustrates shows how at 180 degree rotation, light from theilluminator is projected at the bottom of the area of biometricacquisition.

FIG. 13 shows a profile view of the tilted mirror, showing how lightprojected at position 1 will provide a vertical scan, and lightprojected at position 2 will provide a horizontal scan.

FIG. 14 illustrates a projected guide-path on the ground at time instant1

FIG. 15 illustrates a projected guide-path on the ground at time instant2, such that there is a difference in the projection in order to attractattention to the preferred path and position for the user

FIG. 16 illustrates a video screen A showing one of video of the person,moving images, text, in order to attract attention as the user walksforward

FIG. 17 illustrates a configuration of cameras and illuminatorsaccording to the invention.

FIG. 18 illustrates an embodiment of the invention where the housing isfurther from the subject

FIG. 19 illustrates a projection of a guide light on the floor.

FIG. 20 illustrates a high level system control according to theinvention.

FIG. 21 illustrates illumination at lower levels being used foracquiring biometric data other than iris.

FIG. 22 illustrates an illumination control sequence where wide andsingle spectrum data is acquired.

FIG. 23 illustrates standard access control architecture wheremanagement software stores user data and a standard processor stores asubset thereof.

FIG. 24 is the system of FIG. 23 modified to include an additionalbiometric processor.

FIG. 25 is the system of FIG. 24 with functions of the standardprocessor being assumed by the biometric processor.

DETAILED DESCRIPTION

While the invention is capable of many embodiments, for purposes ofillustration a few embodiments are described below with reference to thedrawings wherein FIG. 1 illustrates a subject 11 walking towardscombined camera and stroboscopic illuminator housing 12 mounted above adoorway 13.

FIG. 2 illustrates swept volume of subject 11 in three sections. Theswept volume is a term referring to the three dimensional volume formedby a two dimensional section of a subject as it moves forward in arelatively straight line. In the case of FIG. 2, the subject 11 walksforward toward the doorway 13 and then through doorway 13. Imagery isacquired by the camera during periods when the stroboscopic infraredilluminator is flashed or the illuminator is scanned. The subject mayalternatively be transported in the case of a moving floor or sidewalkor in the case of a wheelchair, cart, train, or other means oftransporting the subject forward in a relatively straight line. Thefirst section 14 of the swept volume is before image acquisition; thesecond section 15 of swept volume is during image acquisition; and thethird section 16 is after image acquisition, including as the subjectpasses through the doorway 13.

FIG. 3 illustrates an alternative embodiment wherein the housing 12 islocated on the side of doorway 13.

FIG. 4 illustrates an alternative embodiment wherein two housings, 12 aand 12 b, are employed, with housing 12 a on located on the left sideand housing 12 b located on the right side of doorway 13. Housing 12 amay contain one or more cameras and/or illuminators, and housing 12 bmay contain one or more cameras and/or illuminators.

FIG. 5 illustrates another alternative embodiment wherein the housing 12is mounted on a support 17 to the right of the path of the subject 11.Although swept volume 14, 15, 16 is not illustrated in FIG. 5, the sameswept volume as illustrated in FIG. 2 applies to the embodiment of FIG.5. In this embodiment, the doorway 13 is closed, but would be opened orunlatched by the system of the invention if biometric matchingidentifies the subject 11 as authorized to pass through doorway 13.

FIG. 6 illustrates an embodiment wherein the housing 12 is mounted at adistance 18 above the floor or ground 17, with mount 19 supporting thehousing from an overhead structure (not shown). In this embodiment, thehousing has no contact with the ground 17.

FIG. 7 illustrates a face 20 within an area 21 of biometric acquisition,i.e., the area over which the camera(s) are adapted to view. Thecamera(s) has/have a field of view 21 at a particular instant whereinthe face 20 of the subject must pass for biometric acquisition to occur.

FIG. 8 (comparative) illustrates a prior art embodiment wherein astroboscopic illuminator illuminates the whole area 21 as disclosed inU.S. Pat. No. 4,762,410, which is much larger, relatively, than the areaof the subject's face 20.

FIG. 9 illustrates an embodiment of the invention wherein theilluminator(s) are not strobed but rather are either moved or theirillumination is redirected. A preferred method is to move theillumination by one or more mirrors. In this embodiment, substantiallyrectangular area of illumination 23 having a height 24 is scannedsubstantially in direction 22 using a moving mirror so that that lightis only on the eye area of face 20 for a short time. Fewer illuminatorsare required, high-power pulsed operation is not required in thisembodiment, resulting in less stress to the illuminator components andlower cost components.

FIG. 10 illustrates an alternative embodiment wherein substantiallyrectangular area 23 is much smaller than as illustrated in FIG. 9,having a width 25 which is much smaller than in FIG. 9, and wherein thearea of illumination 23 is scanned left to right and then right to leftin a zigzag pattern 26 so as to cover the entire area 21 starting withone corner and zigzagging across and down, and then repeating thezigzagging. In this embodiment, the area of interest is only illuminatedfor a fraction of the time of the illumination.

FIG. 11 illustrates an area of biometric acquisition 21 which isilluminated by illumination 32 which originates from illumination module27 through lens 28. The illumination 31 originating at lens 28 isdirected toward mirror 29 which is rotated by motor 30, causing theillumination 32 to scan according to the pattern illustrated in FIG. 9.

FIG. 12 illustrates the redirection of illumination 31 coming frommirror 29 when the mirror 29 is at 180 degree rotation and light isprojected down area 21.

FIG. 13 illustrates an elevational cross sectional view of mirror 29 anddirection of rotation 33, wherein illumination can be directed to eitherof two areas, 1 or 2, and reflected light would be projected eitherhorizontally or vertically when mirror 29 is rotated.

FIG. 14 illustrates subject 11 walking toward doorway 13 above whichhousing 12 is mounted, with arrow 34 projected on the floor.

FIG. 15 illustrates arrow 34 projected closer to the door at a secondinstant in time, the projected arrow moving in order to attractattention of subject 11 to the preferred path and position for biometricacquisition.

FIG. 16 illustrates an embodiment which includes a video screen 35adapted to show video of the person, moving images, and/or text, inorder to attract attention as the user walks forward and cause thesubject to look toward the housing 12.

FIG. 17 shows a particular configuration of lenses, cameras andilluminators that are mounted approximately in the same plane above orin front of the user. For both face and iris recognition, light istransmitted from the illuminators, reflected off the face and/or iristhrough the camera lens and onto the image plane of one or more cameras.The advantage of having lenses, cameras and illuminators mounted inapproximately the same plane is that the device is compact, but thedisadvantage is that the specular reflections off glasses can occludeall or portions of the face or eye. U.S. Pat. No. 6,540,392 describesthe problem in a micro-illuminator application, where the illuminator isvery small. The illuminator can typically be configured to be small onlywhen the user is very close to the device, which is a situation thattypically results in the device being uncomfortable to use.

FIG. 18 shows an example where the illuminators and cameras aresignificantly further from the user, in order to make the system morecomfortable for the user. The figure shows a subject standing in frontof a camera at a distance h, head-position offset from the camera by adistance d, head-orientation offset from the camera direction by theta,and with an illuminator at a distance D from the camera as shown. In thecase of near-flat glasses, then the geometrical relationship between theparameters defines the configurations where occlusion is expected. Morespecifically, phi=a Tan(d/h), and Tan(2.theta+phi)=(D−d)/h. If a personis walking while biometric data is being recorded, then the typicalamplitude of the variation in head orientation of a person is recordedto be approximately 2 degrees [“Interaction of the body, head and eyesduring walking and turning”, Imai, Moore, Raphan, Experimental BrainResearch (2001), 136:1-18], and this constrains the optimalconfiguration. For example, in one configuration, with h=1.2 m, d=0.06m, then D can be chosen to be at least 0.3 m, so that theta can vary byup to 4 degrees (x2 margin of error) before occlusion will occur.Additional illuminators can be added, for example, on the opposite sideof the camera and subjected to the same calculation by symmetry.

FIG. 19 illustrates a user-guide light can optionally be projected ontothe ground when the presence of the user is detected. This encouragesthe user to walk through the projected light so that the position of theface or eye of the user is optimal for biometric acquisition withrespect to the camera and other components. The presence of the user maybe detected using a microwave or infrared motion sensor. The pattern maybe projected on the ground using standard illuminators with maskedpatterns.

FIG. 20 shows the high-level system control. The approaching user isdetected by the Presence Detector module. If presence is detected thenthe guidance controller initiates the projected illumination.Optionally, audio instructions are provided. An image acquisitionprocess is then performed, which includes a step of turning onillumination. A biometric template is extracted from the image andcompared to templates stored in the database by the Biometric Matchingmodule. Results of the biometric matching are then passed immediately tothe Result Processor module which then sends information to the GuidanceController to inform the user that they are authorized, unauthorized, orneed to repeat the acquisition process. In parallel, the ResultProcessor optionally sends information to an Access Control System whichcontrols an Actuator to physically disengage a lock, for example.

Presence Detector modules have been used previously but such detectorsdo not localize the user position well, and do not localize theorientation of users at all. For example, in an airport application, thebiometric system may be at a boarding gate in order to verify theidentity of boarding passengers, but in fact numerous passengers can bewalking orthogonal to the device while in transit to other gates,thereby triggering the infrared or microwave detectors continuously. Inanother example, a stream of users, each behind each other, may becontinuously using the device. This will result in the Presence Detectorbeing continually triggered. Since the Presence Detector triggers theillumination, the illumination will be continually turned on. Thisgreatly increases the degree to which subjects, particularly staffstanding continuously by the device, are irradiated. It also reduces thelifetime of the illuminators.

FIG. 21 shows a solution where the illumination is continually on, butat a greatly reduced level. The illumination level is typically notsufficient for reliable biometric matching, but can be sufficient fordetection of the potential presence of biometric features (face or eye,for example) in the module called Mid-Confidence Feature Detector. Ifsuch a feature is detected, then a control signal is sent to theIllumination Controller to increase the illumination to the desiredlevel only for the number of frames required to acquire the biometricdata. For example, only 2-3 frames may be required to ensure that datawas acquired reliably. The images acquired under high-power illuminationare then processed by a High-Confidence Feature Detector and then storedin a Queue ready for biometric match processing. This approach will onlytrigger on a person who is facing the system and is ready for biometricacquisition. The approach has the advantage of irradiating the immediatearea of the device with the minimum illumination required for biometricacquisition, which increases the lifespan of the illuminators andminimizes the degree to which staff nearby are irradiated.

We also describe fraud-resistance in order to prevent a user frompurporting to be another user. For example, photographs of the face oriris can sometimes be used in place of the user's face or iris in orderto purport to have another identity. Several methods have been proposedto detect fraud detection. For example, U.S. Pat. No. 6,760,467describes a method for turning on and off 2 illuminators to detect if alive-eye is in the scene by determining if the specularity from theilluminator is present in the acquired image at the expected time. Inanother method, it is known that skin and other living tissue has aparticular spectral signature that can be differentiated from paper orother synthetic material. This approach either requires multiple sensorsto acquire data through spectral filters at the same time, or requires asingle sensor to acquire data under different spectral illumination atdifferent times. However, while we wish to acquire single-spectrum datato analyze the spectral signature, we still wish to acquire widespectrum data that can be reliably used for biometric matching.

FIG. 22 shows an illumination control sequence that optimizes theacquisition of wide spectrum data with single spectrum data. The primaryimage acquisition loop is on the left. A counter N increments as eachframe is acquired and then is reset back to 0 when it reaches a maximumvalue, which is S in the case presented. The counter N is used to selecta previously-stored illumination configuration. The graphs on the rightshow illumination sequences that optimize the acquisition of widespectrum data with single spectrum data in the case of 3 illuminationfrequencies. Full-spectrum illumination is present when each alternateframe is acquired, and these images can be used for biometric matching.Each single spectrum illumination is cycled through one-by-one in theremaining frames. In the case of 3 illumination wavelengths, this meansthat every 2 frames there is data suitable for biometric matching, whileevery 6 frames there is data suitable for liveness detection. Thequality of the data required for biometric matching is typically higherthan that required for liveness detection and therefore the fullspectrum data is acquired at the higher acquisition rate. This methodcan be extended to use a different number of wavelengths. For example,if 4 wavelengths are used, then every 2 frames there is data suitablefor biometric matching, while every 8 frames there is data suitable forliveness detection.

We also describe a back-end biometric architecture that allows abiometric device to be integrated to a non-biometric architecturewithout losing the additional functionality that the biometric deviceenables, and where either type of device can be managed and deployed inthe same way. More specifically, most biometric architectures have beendeveloped to optimize biometric performance with minimal or noconsideration of the large base of installed non-biometric devices andarchitectures, and have assumed that integrators will be speciallytrained to integrate biometric devices. These are amongst the factorsthat have limited the widespread deployment of biometric devices. Asdiscussed later, this is especially relevant when a biometric device isused to compare a biometric template acquired from a user with more thanone template in the database (recognition) as oppose to comparing atemplate with just one candidate template in the database(verification).

In the case of verification, a card-swipe of other means ofidentification sends a small set of data to a processor for one-to-onecomparison. In the case of recognition however, the processor needs tobe capable of performing one-to-many comparisons rapidly, and thecomparisons are typically not simple digit matching—they are biometrictemplate matching, which typically takes substantially more processing.As a result, custom biometric match processors have been developed toperform the biometric matching. However, these custom match processorshave biometric databases that are typically managed separately from thestandard database that may already exist at a deployment. We propose anarchitecture where non-biometric devices and biometric devices canco-exist in the same architecture without any loss of functionality, andwhere either type of device can be managed and deployed in the same way.

FIG. 23 shows a standard access control architecture where ManagementSoftware stores all user data with access permissions, and the StandardProcessor stores a subset of that data. The one-to-one useridentification method (e.g. card swipe) is connected to the StandardProcessor and the result of the processing is then user to controlentry, for example.

FIG. 24 shows the same architecture, but an additional BiometricProcessor has been added, together with 1 or more Biometric AcquisitionDevices. The Management Software communicates to both the StandardProcessor and the Biometric Processor using the same protocols and fieldformats, except the Biometric Processor is receptive to an additionalfield which contains the user's biometric information. The BiometricAcquisition Device and the Biometric Processor communicate usingspecific protocols in order to pass biometric template information. Theoutput of the Biometric Processor uses the same protocols and fieldformats as a nonbiometric acquisition device, such as a card swipe, eventhough the data was derived from use of the Biometric AcquisitionDevice. This data can then be fed directly to the Standard Controller,thereby enabling all the existing Management Software functions to beperformed seamlessly even on biometrically-derived data. This approachallows biometric devices capable of recognition to be added seamlesslyto systems that comprise nonbiometric devices without any loss offunctionality, and where either type of device can be managed anddeployed in the same way.

FIG. 25 shows an additional architecture that shows how the functions ofthe Standard Processor are assumed by the biometric-enabled Processor.

The preferred distance between the camera or cameras and the subject atthe time of acquiring biometric data depends on the particularapplication. For example, when there is no equipment in the way, thepreferred horizontal distance is 0.45 m to 3.15 m where the camera orcameras are mounted above the swept-volume, for example inaccess-control at doorways, identification at airports, border crossingsand hotels. For certain embodiments where one or more cameras aremounted above or to one side of the swept volume, the preferred distanceis 0.3 m to 5.72 m such that the angle between the optical axis of theone or more cameras and a vector defining the path of the swept volumeis less than approximately 45 degrees, for example for identificationthrough windshields of cars, as well as access-control at doorways,identity validation at airports, border crossings or hotels wheremounting of cameras from above is not preferred. For certain embodimentswhere one or more cameras are mounted to one side of the swept volume,such that the angle between the optical axis of the one or more camerasand a vector defining the path of the swept volume is greater thanapproximately 45 degrees, a preferred distance is 0.1 m to 2.8 m forexample in border control lanes and point-of-sale terminals. A distanceof 0.1 to 5.72 m is preferred for certain embodiments for access-controlat doorways, identification at airports, border crossings and hotels,identification through windshields of cars, border control lanes,point-of-sale identification, and desk-based or kiosk-basedidentification, or identification using a substantially mobile device,especially the where illumination is scanned.

In embodiments wherein the housing 12 is placed above a doorway orportal, the biometric data is preferably acquired when the horizontaldistance between the subject and at least one of the cameras is between97.28 and 201.93 cm.

The present invention, therefore, is well adapted to carry out theobjects and attain the ends and advantages mentioned, as well as othersinherent therein. While the invention has been depicted and describedand is defined by reference to particular preferred embodiments of theinvention, such references do not imply a limitation on the invention,and no such limitation is to be inferred. The invention is capable ofconsiderable modification, alteration and equivalents in form andfunction, as will occur to those ordinarily skilled in the pertinentarts. The depicted and described preferred embodiments of the inventionare exemplary only and are not exhaustive of the scope of the invention.Consequently, the invention is intended to be limited only by the spiritand scope of the appended claims, giving full cognizance to equivalentsin all respects.

What is claimed is:
 1. A system for acquisition of biometric data from a subject, the system comprising: at least one light source configured to: illuminate a subject with light pulses from a first spectrum and a second spectrum of a plurality of discrete light spectra, and illuminate the subject with light pulses from the second spectrum of the plurality of discrete light spectra, the second spectrum different from the first spectrum; a sensor configured to acquire, at a first rate of acquisition, a set of iris data from the subject for biometric matching, using the light pulses from the first spectrum and the second spectrum, and acquire at a second rate of acquisition that is lower than the first rate of acquisition and interleaved with the acquisitions at the first rate of acquisition, a set of biometric data from other than an eye or iris of the subject for liveness detection, using the light pulses from the second spectrum; and at least one processor configured to perform biometric matching using data from the set of iris data, and liveness detection using the set of biometric data.
 2. The system of claim 1, wherein the sensor is further configured to acquire, at a third rate of acquisition interleaved with the acquisitions of the set of iris data and the set of biometric data, another set of biometric data from the subject, using light pulses from a third spectrum of the plurality of discrete light spectra.
 3. The system of claim 1, wherein the sensor is further configured to acquire some of the iris data from the subject while the subject is in motion.
 4. The system of claim 1, wherein each of the plurality of discrete light spectra comprises light of a single wavelength.
 5. The system of claim 1, wherein each of the light pulses from the first spectrum and the second spectrum is formed from a light pulse from the first spectrum and a light pulse from the second spectrum.
 6. The system of claim 1, wherein the sensor is configured to acquire the set of iris data with an image quality higher than that of the set of biometric data.
 7. The system of claim 1, further comprising at least one processor configured to detect a spectral signature consistent with skin or living tissue using the set of biometric data.
 8. The system of claim 1, wherein the sensor is configured to acquire the set of iris data using light from a spectrum wider than the second spectrum.
 9. A method for acquisition of biometric data from a subject, the method comprising: illuminating a subject with light pulses from a first spectrum and a second spectrum of a plurality of discrete light spectra; acquiring, by a sensor at a first rate of acquisition, a set of iris data from the subject for biometric matching, using the light pulses from the first spectrum and the second spectrum; illuminating the subject with light pulses from the second spectrum of the plurality of discrete light spectra, the second spectrum different from the first spectrum; acquiring, by the sensor at a second rate of acquisition that is lower than the first rate of acquisition and interleaved with the acquisitions at the first rate of acquisition, a set of biometric data from other than an eye or iris of the subject for liveness detection, using the light pulses from the second spectrum; and performing biometric matching using data from the set of iris data and liveness detection using the set of biometric data.
 10. The method of claim 9, further comprising acquiring, by the sensor at a third rate of acquisition interleaved with the acquisitions of the set of iris data and the set of biometric data, another set of biometric data from the subject, using light pulses from a third spectrum of the plurality of discrete light spectra.
 11. The method of claim 9, further comprising acquiring some of the iris data from the subject while the subject is in motion.
 12. The method of claim 9, wherein each of the plurality of discrete light spectra comprises light of a single wavelength.
 13. The method of claim 9, wherein each of the light pulses from the first spectrum and the second spectrum is formed from a light pulse from the first spectrum and a light pulse from the second spectrum.
 14. The method of claim 9, further comprising acquiring the set of iris data with an image quality higher than that of the set of biometric data.
 15. The method of claim 9, further comprising detecting a spectral signature consistent with skin or living tissue using the set of biometric data.
 16. The method of claim 9, wherein acquiring the set of iris data from the subject comprises acquiring the set of iris data using light from a spectrum wider than the second spectrum. 